Concept

Cosmic distance ladder

Related publications (185)

The formation of the Milky Way halo and its dwarf satellites: A NLTE-1D abundance analysis. V. The Sextans galaxy

Pascale Jablonka

We present a homogeneous set of accurate atmospheric parameters for a sample of eleven very metal-poor (-3.32

OXFORD UNIV PRESS2021

Baryon acoustic oscillations in the projected cross-correlation function between the eBOSS DR16 quasars and photometric galaxies from the DESI Legacy Imaging Surveys

Cheng Zhao, Anand Stéphane Raichoor

We search for the baryon acoustic oscillations in the projected cross-correlation function binned into transverse comoving radius between the SDSS-IV DR16 eBOSS quasars and a dense photometric sample of galaxies selected from the DESI Legacy Imaging Survey ...

OXFORD UNIV PRESS2021

CODEX weak lensing mass catalogue and implications on the mass-richness relation

Jean-Paul Richard Kneib, Huanyuan Shan

The COnstrain Dark Energy with X-ray clusters (CODEX) sample contains the largest flux limited sample of X-ray clusters at 0.35 < z < 0.65. It was selected from ROSAT data in the 10 000 square degrees of overlap with BOSS, mapping a total number of 2770 hi ...

OXFORD UNIV PRESS2021

Measuring accretion disk sizes of lensed quasars with microlensing time delay in multi-band light curves

Frédéric Courbin, Martin Raoul Robert Millon, Hung-Hsu Chan, Vivien François Bonvin, Karina Alexandra Rojas Olate

Time-delay cosmography in strongly lensed quasars offers an independent way of measuring the Hubble constant, H-0. However, it has been proposed that the combination of microlensing and source-size effects, also known as microlensing time delay, can potent ...

EDP SCIENCES S A2021

Learning convergence prediction of astrobots in multi-object spectrographs

Denis Gillet, Jean-Paul Richard Kneib, Matin Macktoobian, Francesco Basciani

Astrobot swarms are used to capture astronomical signals to generate the map of the observable universe for the purpose of dark energy studies. The convergence of each swarm in the course of its coordination has to surpass a particular threshold to yield a ...

2021

Weak-lensing mass reconstruction using sparsity and a Gaussian random field

Austin Chandler Peel

Aims. We introduce a novel approach to reconstructing dark matter mass maps from weak gravitational lensing measurements. The cornerstone of the proposed method lies in a new modelling of the matter density field in the Universe as a mixture of two compone ...

2021

Reducing the variance of redshift space distortion measurements from mock galaxy catalogues with different lines of sight

Cheng Zhao

Accuratemock catalogues are essential for assessing systematics in the cosmological analysis of large galaxy surveys. Anisotropic two-point clustering measurements from the same simulation show some scatter for different lines of sight (LOS), but are on av ...

OXFORD UNIV PRESS2021

The impact of the fiducial cosmology assumption on BAO distance scale measurements

Cheng Zhao, Paul Carter

Standard analysis pipelines for measurements of Baryon Acoustic Oscillations (BAO) in galaxy surveys make use of a fiducial cosmological model to guide the data compression required to transform from observed redshifts and angles to the measured angular an ...

OXFORD UNIV PRESS2020

Improving baryon acoustic oscillation measurement with the combination of cosmic voids and galaxies

Andrei Variu, Cheng Zhao, Yu Liang

We develop a methodology to optimize the measurement of baryon acoustic oscillation (BAO) from a given galaxy sample. In our previous work, we demonstrated that one can measure BAO from tracers in underdense regions (voids). In this study, we combine the o ...

OXFORD UNIV PRESS2020

Photometric characterization of multiple populations in star clusters: the impact of the first dredge-up

Carmela Lardo

The existence of star-to-star light-element abundance variations (multiple populations, MPs) in massive Galactic and extragalactic star clusters older than about 2 Gyr is by now well established. Photometry of red giant, branch (RGB) stars has been and sti ...

OXFORD UNIV PRESS2020

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